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Primary Side Transformer Used to create 110 V

Primary Side Transformer Used to create 110 V

Primary Side Transformer Used to create 110 V

Let me start by saying, I am NOT an electrical engineer. Been an electrician off and on for 40+ years, residential & commercial wiring, troubleshooting, not half bad at reading schematics but that is it. Recently ran into a situation in a Brunswick Pinsetter power supply box. They use a double coil primary, (Can be either 110 or 220V depending if wired in parallel or series). Mine are wired for 220V so H1 & H4 are the line supply phases. They "tap" between H1 & H2 to supply 110V to both a contactor coil & selenium rectifier and between H3 & H4 to supply a 110V pin light ballast. I realize it works as you read 110V from H1-H2 and H3-H4 but it just doesn't seem right as there is no "real neutral". In addition there is NO Neutral bar in the electrical box, only two Hots and a ground, (basically the old 3-wire system as these were designed in the 1950'S). Won't these additional loads on the Primary Side cause havoc with the secondary voltages,(24-28V), circulating current, etc.?? Included the schematic. Thanks for the help.

RE: Primary Side Transformer Used to create 110 V

As you said, it works.

Mike Halloran
Pembroke Pines, FL, USA

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